Apparatus for collecting sludge from the floor of a settler basin

ABSTRACT

A system meets needs in sludge collection by significantly increasing the flow rate through a header that collects sludge without causing problems in priming. Telescopic pipes stay in a line adjacent to the bottom of a basin and do not float upwardly into or against equipment in the basin. The entire sludge collecting system is in a space of a low-clearance height under the equipment that extends downwardly near the bottom of the basin. The sludge is collected by openings in header pipes, and by at least one bearing opening in an outer pipe, wherein the bearing opening extends to a radial clearance between the telescopic pipes. Flow of the sludge through the radial clearance from the bearing opening is allowed by a bearing that permits relative movement of the outer pipe and the inner pipe to allow traversing of the outer pipe.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of application Ser. No. 10/420,570filed Apr. 21, 2003 now U.S. Pat. No. 6,951,620 for “Apparatus andMethod For Collecting Sludge From The Floor Of A Settler Basin” (the“parent application”), priority from which parent application Ser. No.10/420,570 is claimed under 35 USC Section 120, and which parentapplication is incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to the collection of materials fromliquids, and more particularly to a telescopic pipe arrangement carryinga sludge collector header in a material collection basin.

BACKGROUND OF THE INVENTION

In the past, containers (e.g., basins or tanks) have been provided tohouse apparatus in which materials are collected. For example, materialsmay be collected from liquids by plate or tube settlers that promotesettling of the material to the bottom of the basin. In other cases,flocculators may be housed in such containers, and materials ofteninadvertently move in the flocculators to the bottom of the basin.Because the flocculators are designed to circulate the liquid andmaterials, rather than promoting settling of the materials, thematerials that inadvertently collect at the bottom of the basin presenta problem. In both cases, the materials on the bottom may be referred toas sludge.

In the case of the settlers, for example, the sludge is collected, orremoved, from the bottom to make room for more materials as more liquidand materials flow into the basin. In the past, sludge collectionequipment has been mounted on or near the bottom for gathering thesludge and flowing the sludge out of the basins. Such equipment hasincluded a so-called header pipe (e.g., a hollow tube) mounted formovement along a path adjacent to the bottom. The header pipe is belowthe settler plates of a settler, for example. Low pressure has beenapplied to the header pipe as the header pipe moves along the path.Holes in the pipe admit the sludge and liquid from the bottom of thebasin. The holes may be of the type described in U.S. Pat. No.5,914,049, issued on Jun. 22, 1999, and entitled “Method and ApparatusFor Helical Flow In Header Conduit”, the disclosure of which isincorporated by reference. Under the action of the low pressure, thesludge and the liquid flow into and through the header pipe, and fromthe header pipe through a flexible outlet hose to a discharge locationout of the basin.

The low pressure has been applied to the header pipe by the flexibleoutlet hose. Such hoses have generally been small diameter hoses, e.g.,not exceeding four inches in diameter. Also, the flexible hoses aretypically ribbed on the inside, which restricts the inside diameter andincreases head loss. Generally, such small diameter hoses can onlyinduce a maximum flow rate of about 200 gallons per minute (gpm) in theheader pipe. Thus, the flow rate through the header pipe has beenlimited by the flow capacity of the flexible outlet hoses.

An unacceptable solution to this flow rate problem is to use many of theflexible hoses. That solution is unacceptable because the flexibleoutlet hoses can flex. Each flexible hose is thus free to rise (i.e.,float) above the header pipe under buoyancy forces of gases in theflexible outlet hose. As a result, the flexible hoses have in the pastrisen above the header pipe and a portion of each flexible hose hasassumed an inverted U-shape. Unfortunately, because the U-shaped portionis above the level of the header pipe, and is above the level of anoutlet of the flexible hose from the basin, the gas becomes trapped insuch inverted U-shaped portion, making it difficult to prime the hosewhen starting the sludge collecting operation. When many flexible hosesare used to provide more flow rate from the header, the priming problemis increased.

Also, because the flexible outlet hoses tend to float, these hoses tendto interfere with the operation of the settlers, which extend downwardlyin the basin toward the bottom and provide a low-clearance situation atthe bottom of the basin. A similar problem would exist with attempts touse such hoses to remove the material from beneath the flocculators.

What is needed then is a way of significantly increasing the flow ratethrough a header pipe that collects material from the bottom withoutcausing problems in priming the sludge collection system. What is alsoneeded is a way to achieve such sludge collection, while having aneasily primed collection system, and to provide the entire sludgecollecting system in the low-clearance space under settler, flocculatingand related equipment that extends down near the bottom of the basin.What is further needed, then, is to achieve these features, while stillallowing the sludge collecting system to traverse the header from oneend of the basin to the opposite end of the basin. What is still furtherneeded then, is to achieve these features, while allowing the sludgecollecting system to traverse the header from one end of a very longbasin to the opposite end of the very long basin. What is finally neededthen, is to achieve these features, while allowing the sludge collectingsystem to both traverse the header from one end of a very long basin tothe opposite end of the very long basin, and to collect the materialfrom the basin at a central location between opposite ends of theheaders.

SUMMARY OF THE INVENTION

Briefly, embodiments of the present invention meet all of the aboveneeds by providing a way of significantly increasing the flow ratethrough a header pipe that collects material from the bottom withoutcausing the problems in priming the sludge collection system, and whilecollecting the material from the basin at a central location betweenopposite ends of the header pipe. The embodiments of the presentinvention also provide a way of achieving such sludge collection, whilehaving an easily primed collection system, and providing the entiresludge collecting system in the low-clearance space under the settlerand flocculating equipment that extends down near the bottom of thebasin.

The way of significantly increasing the flow rate through a header pipethat collects material from the bottom is by using a larger-diameterpipe assembly connected to the header pipe. The way of avoiding problemsin priming the sludge collection system is by making the larger-diameterpipe assembly rigid so that it is not free to rise (float) above thelevel of the header pipe in the basin, or the outlet of the pipeassembly, which is near the bottom of the basin. The way of achievingsuch sludge collection, while having an easily primed collection system,and providing the entire sludge collecting system in the low-clearancespace under the settler and flocculating equipment that extends downnear the bottom of the basin, is to mount the larger-diameter, rigidpipe assembly directly adjacent to the bottom of the basin, e.g., alongthe path normally taken by the header pipe as it traverses the bottom ofthe basin. The way of achieving these features, while still allowing thesludge collecting system to traverse the header from one end of thebasin to the opposite end of the basin, is by making the larger-diameterrigid pipe assembly telescopic, that is, in two parts that have atelescopic relationship. In this manner, one telescopic pipe may besecured or fixed to the basin, as by being held in place as it extendsthrough an end wall of the basin to a sludge outlet outside the basin.Such fixed pipe may be a larger-diameter pipe, measured relative to thesmall (e.g., maximum of four inches) prior flexible hoses describedabove. The other telescopic pipe may be somewhat larger (e.g., about twoinches larger) than the fixed pipe so as to receive the fixed pipe andpermit relative movement between the two telescopic pipes. The othertelescopic pipe may be called the outer, or movable, telescopic pipe.The movable pipe carries one or more of the headers and may be moved bya low-profile cable drive relative to the bottom of the basin andbetween the end walls of the basin to present the headers to the sludgethat accumulates on the bottom of the basin awaiting collection. The wayof achieving these features, while allowing the sludge collecting systemto traverse the header from one end of a very long basin to the oppositeend of the very long basin, is to have the inner pipe extend fullybetween the opposite end walls of the very long basin and be a guide forthe outer pipe that defines part of a conduit for collecting thematerial and liquid that are to be directed out of the basin. The way ofachieving these features, while allowing the sludge collecting system toboth traverse the header from one end of a very long basin to theopposite end of the very long basin and to collect the material from thebasin at central location between opposite ends of the headers, is toconfigure a bearing between the telescopic pipes so as to allowadditional flow of the material in a radial clearance that is betweenthe telescopic pipes and in which the bearing is received. In thismanner, an open end of the movable, large-diameter, outer pipe serves asan additional material collector positioned at a central location thatis between opposite ends of the header pipe.

One aspect of the embodiments of the present invention is to provide asystem for collecting material in which a first rigid pipe and a secondrigid pipe each define a conduit. The first and second pipes are intelescopic relationship, one received within the other so that theconduits of the pipes cooperate to define a material collection conduit.Headers may be secured to one of the rigid pipes and generally haveopenings through which to collect the material. The headers defineheader conduits extending from the header openings to the conduit of theone rigid pipe to carry the material to the material collection conduit.

Another aspect of the embodiments of the present invention is to providethe system for collecting material with a bearing positioned between thefirst pipe and the second pipe. With the pipes operated at low pressure,the bearing reduces the flow of the material into the materialcollection conduit from other than the header openings, and thus allowsthat material flow into the material collection conduit from other thanthe header openings. Because the header openings are spaced across awidth of the basin and the bearings move with the first pipe, thebearing promotes sludge collection centrally between the opposite endsof each header, and the headers collect material across the width of thebasin. The bearing also permits relative movement between the pipes inthe telescopic relationship, and thus promotes the traversing of theheaders.

Another aspect of the embodiments of the present invention is to providethe system for collecting material in a basin configured with a bottomto contain the material. The first pipe and the second pipe aresupported on the bottom of the basin. The first pipe is the one of thepipes to which the headers are secured, the second pipe being the onepipe received in the other pipe. The second pipe is secured to thebasin. The first pipe is movable relative to the basin and to the secondpipe so that the material collection conduit is extendable andretractable as the first pipe moves relative to the basin. Theextendable and retractable material collection conduit carries collectedmaterial from the header opening to the first conduit of the first pipeand to the second conduit of the second pipe.

Still another aspect of the embodiments of the present invention is toprovide the system for collecting material with an exemplary twoheaders. One of the two headers is positioned adjacent to one end of thefirst pipe and the other of the two headers is positioned adjacent tothe other end of the first pipe.

Yet another aspect of the embodiments of the present invention is toprovide the system for collecting material with one header, and thefirst pipe is configured with a bearing end. The first pipe movesrelative to the second pipe and is configured with a header support endsecured to the header, the header support end being spaced from thebearing end. The one header is positioned at the header support end ofthe first pipe.

One other aspect of the embodiments of the present invention is toprovide the system for collecting material with a drive connected to thefirst pipe, the drive being configured to move the first pipe relativeto the basin and to the second pipe.

One further aspect of the embodiments of the present invention is toprovide the system for collecting material wherein the materialcollection conduit is configured to carry a flow of the material of fromabout 20 gpm to about 2000 gpm, and the material collection conduit isconfigured with a minimum diameter of from about 3 inches to about 12inches.

Still another aspect of the embodiments of the present invention is toprovide the system for collecting material in a basin having a bottomfor supporting the material, the basin being configured with equipmentthat provides the material supported on the bottom. The equipment may beconfigured in a position relative to the bottom to provide low-clearanceheight between the bottom and a lower portion of the equipment. Thesystem may include a low-profile apparatus for collecting the materialfrom the bottom of the basin. The low-profile apparatus includes a firstrigid pipe. The first rigid pipe defines a first conduit. A second rigidpipe defines a second conduit. The first and second pipes are intelescopic relationship, with the second pipe being received within thefirst pipe so that the first and second conduits of the pipes cooperateto define a material collection conduit. The material collection conduitextends generally parallel to the bottom of the basin and in thelow-clearance height between the equipment and the bottom. One or moreheaders are secured to the first pipe. The headers have openings throughwhich to collect the material. Each header defines a header conduitextending from the openings to the respective conduits of the rigidpipes to carry the material to the material collection conduit. Tofacilitate the collection, the low-profile apparatus may further includea low-profile drive connected to the first pipe, the drive beingconfigured to move the first pipe relative to the basin and to thesecond pipe. The drive of the low-profile apparatus may be configuredwith a cable secured to the first rigid pipe and extending along thebottom under the equipment to move the first pipe relative to the basinand to the second pipe and under the equipment in the basin. Also, abearing may be positioned between the first pipe and the second pipe topromote flow of the material from the headers to the material collectionconduit defined by the pipes. The bearing is positioned inside the firstpipe and outside the second pipe, the bearing also permitting both (1)relative movement between the pipes in the telescopic relationship, and(2) flow of the material into a space between the first and secondpipes, where the flow is about equal to the flow into one or two of theopenings that are provided in the headers.

A related aspect of the embodiments of the present invention is that thesystem is configured to be used in a basin having spaced first andsecond end walls, and the second rigid pipe is configured to extend fromthe first end wall to the second end wall. In this aspect, the firstpipe may be configured to extend in the telescopic relationship withrespect to the second pipe along a distance greater than half a lengthof the basin between the end walls. The second pipe may also beconfigured with a material collection opening through which to receivethe material from the first pipe.

A still other related aspect of the embodiments of the present inventionis that the first and second pipes are configured so that in thetelescopic relationship the first pipe has opposite ends, and the firstpipe is always outside and coaxial with at least a portion of the secondpipe. In this aspect, a bearing is provided at each of the opposite endsof the first pipe. The bearing promotes both (1) flow of the materialfrom a basin through headers carried by the first pipe, and (2) flow ofthe material into a space between the first and second pipes, where thelatter flow is about equal to the flow into one or two of the openingsthat are provided in the headers. The material flows from the headersinto the first pipe and into the space for flow through a materialcollection opening in the portion of the second pipe, so that the secondpipe receives the material from the first pipe for discharge from thebasin.

A yet other related aspect of the embodiments of the present inventionis that the basin is configured with opposed end walls, and the secondpipe is configured to be supported adjacent to each of the end walls.The material collection conduit comprises an opening in the second pipethrough which to receive the material from the first pipe. In thisaspect, the first pipe is configured with a length that exceeds half ofthe length of the basin between the opposed end walls so that theopening in the second pipe is always covered by the first pipe.

Other aspects and advantages of the embodiments of the present inventionwill become apparent from the following detailed descriptions, taken inconjunction with the accompanying drawings, illustrating by way ofexample, the principles of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will be readily understood by thefollowing detailed description in conjunction with the accompanyingdrawings, wherein like reference numerals designate like structuralelements or operations.

FIG. 1A is a perspective view illustrating a system of the embodimentsof the present invention for collecting material;

FIG. 1B is a perspective view illustrating a portion of the system shownin FIG. 1A, wherein flanges on an outer pipe are shown;

FIG. 1C is a cross sectional view taken along line 1C—1C in FIG. 1A,illustrating the insides of telescopic pipes of the system shown in FIG.1A;

FIG. 2A is an elevational view showing the system installed in acontainer, which is typically referred to as a basin;

FIG. 2B is an elevational view showing an outlet end of an inner pipe;

FIG. 3A is an elevational view showing an extended position of the innerand outer pipes in a telescopic relationship;

FIG. 3B is an elevational view showing a cable drive for moving theouter pipe to the right from the extended position shown in FIG. 3A to acollapsed position shown in FIG. 3B;

FIG. 4 is a cross sectional view taken along lines 4—4 in FIG. 2B,showing details of a fastener that secures an annular bearing to theouter pipe; and

FIG. 5 is a view similar to FIG. 2A in which the basin is configuredwith opposed end walls, and the second pipe is configured to besupported adjacent to each of the end walls and is provided with anopening through which to receive the material from the first pipe.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments of an invention are described for significantly increasingthe flow rate through header pipes that collect material from the bottomof a basin, without causing the above-described problems in priming asludge collection system. Telescopic pipe structures provide a way ofachieving such sludge collection, while having an easily primedcollection system, while providing the entire sludge collecting systemin a low-clearance space under the settler and flocculating equipmentthat extends down near the bottom of the basin, and while collecting aflow of the material from the basin into the telescopic pipe structuresat central bearing locations that are between opposite ends of headerscarried by the telescopic pipe structures.

In the following description, numerous specific details are set forth inorder to provide a thorough understanding of the embodiments of thepresent invention. It will be understood, however, to one skilled in theart, that the embodiments of the present invention may be practicedwithout some or all of those details. In other instances, well knownoperations and structure have not been described in detail in order tonot obscure the embodiments of the present invention.

Referring now to the drawings, FIG. 1A illustrates a system 100 of theembodiments of the present invention for collecting material. Thematerial may initially be in, or mixed with, a liquid, such as water orwater-like fluids typically found in settlers, flocculators or otherliquid treatment plants. For example, the material may be theabove-referenced material collected from liquids in plate or tubesettlers that promote settling of the material to the bottom of thebasin. The settlers may be fabricated according to U.S. Pat. No.5,391,306, issued Jun. 21, 1995, and entitled “Settler With PresetOutlet Area Deck and Variable Angle Removable Lamina and Method of UsingSettler”, in which setter plates are movable, for example, and thedisclosure of such Patent is incorporated herein by this reference.Additionally, the material may inadvertently move from the flocculatorsto the bottom of the basin. Whether the materials are from settlers, orflocculators, or from other sources or equipment, the materials may bereferred to as sludge.

In the system, a first rigid pipe 102 and a second rigid pipe 104 eachdefine a conduit 106. The pipes 102 and 104 are configured to be rigid,as compared to the above-described flexible hoses that are light andtend to bend and allow floatation, as described above. Thus, the rigidpipes 102 and 104 do not bend easily, if at all, and are not subject tothe above-noted problems of the flexible hoses. For ease of description,the first rigid pipe 102 and the second rigid pipe 104 may be referredto as “pipes”, without referencing the rigidity, but in each case therigid characteristic (or property) is provided. To achieve suchrigidity, the pipes 102 and 104 are preferably made from plastic such aspolyethylene (PE), polyvinylchloride (PVC), or acrylonitrile butadenestyrene (ABS), for example. To provide more weight per unit length, andthus more resistance to floatation, the pipes 102 and 104 may be madefrom metal. In a most preferred embodiment, the pipes 102 and 104 may bemade from stainless steel. The metal pipes 102 and 104 have the mostweight per unit length and thus resist floatation more than the plasticpipes which have neutral buoyancy. The rigid pipes also have smoothinsides, and without the bends of the flexible hoses are straight andcause less head loss than the flexible hoses.

The second pipe 104 may be referred to as an inner pipe in that it isreceived partially or entirely inside the first pipe 102 in a telescopicrelationship. The first pipe 102 may be referred to as the outer pipe.To provide adequate flow of the collected materials and liquid, theinner pipe 104 may be configured with a nominal (inside) diameter offrom 3 inches to 12 inches, for example. The outer pipe 102 may beconfigured with a nominal diameter that is about 2 inches greater thanthat of the inner pipe 104 when the inner pipe has the 3 inch nominaldiameter, for example. The outer pipe 102 may be configured with anominal diameter that is about 4 inches greater than that of the innerpipe 104 when the inner pipe has the 12 inch nominal diameter, forexample. The larger diameter of the outer pipe 102 provides a radialclearance of about 1 to 2 inches between a wall 108 of the outer pipe102 and a wall 110 of the inner pipe 104. According to the diametersselected for flow rate purposes, the pipes 102 and 104 may have arespective wall 108 and 110 that is thin, such as a wall thickness ofabout 0.083 to about 0.125 inches. Such adequate flow may be in a rangeof from about 20 gpm (corresponding to the 3 inch diameter inner pipe104) to about 2000 gpm (corresponding to the 12 inch nominal diameterinner pipe 104 and 16 inch nominal diameter outer pipe 102). It may thusbe understood that the rigid inner pipe 104 may be sized to provide asubstantially greater flow rate than the maximum 200 gpm flow rategenerally provided by the flexible hose that is subject to the primingproblems described above.

FIG. 1A shows that the first and second pipes 102 and 104 are in thetelescopic relationship, the inner pipe 104 being received partially orfully within the outer pipe 102, with the pipes 102 and 104 in coaxialrelationship. The telescopic relationship is also one in which the pipes102 and 104 are free to move in an axial direction (see arrow 112)relative to each other so that the longest combined, or extended, lengthof the pipes (see LE in FIG. 2B) is about the sum of each separatelength of each pipe 102 and 104. The length LE also corresponds to anextended position of the pipes 102 and 104. In the extended position,the outer pipe 102 overlaps the inner pipes 104 by about four to sixinches, for example. The axial direction 112 of relative movement alsoallows the pipes 102 and 104 to move so that the inner pipe 104 may bealmost fully received within the outer pipe 102, and the combined, orcollapsed, length (see LC in FIG. 2A) of the pipes 102 and 104 is thevalue of the longer of the two pipes. The length LC also corresponds toa collapsed position of the pipes 102 and 104. In this manner, theconduits 106 of the pipes 102 and 104 cooperate to define a materialcollection conduit 120 that has a variable length.

The length of each separate one of the pipes 102 and 104 is generallythe same, and may range from about 20 feet to about 100 feet, whichlength depends on factors described below. The telescopic relationshipbetween the two pipes 102 and 104 is illustrated in FIG. 1A, which showsone part (see C1) of the material collection conduit 120 configured fromthe conduit 106 of the outer pipe 102 when the inner pipe 104 is onlypartially within the outer pipe 102. FIG. 1A shows a second part (seeC2) of the material collection conduit 120 configured from the conduit106 of the inner pipe 104 when the inner pipe 104 is only partiallywithin the outer pipe 102. Part C2 is shown extending partially withinand then to the right of the first pipe 102. The conduit 106 of theinner pipe 104 has the lesser diameter of the two pipes 102 and 104, andmust be sized to provide the desired flow rate of the material and theliquid that are collected. In a different sense, it may be understoodthat the approximate maximum 16 inch nominal diameter of the telescopedpipes 102 and 104 and other factors of the embodiments of the presentinvention may provide a maximum vertical dimension DM (FIG. 3A) of abouttwo feet. This maximum vertical dimension DM is referred to as a lowprofile, wherein “low” designates a value less than a clearance, orheight distance, H (FIG. 3A) described hereinbelow. This low profilealso takes into consideration another factor, namely that the outer pipe102 may be provided and configured as shown in FIG. 1B with an assemblyof short pipes that are connected by flanges 121, for example, such thatthe flanges 121 are within the low profile.

FIGS. 1B and 1C show a bearing 122 in the outer pipe 102. For clarity ofillustration, the bearing 122 is not shown in FIG. 1A. The bearing 122may be configured from polymer. The bearing 122 is configured to bemounted over the inner pipe 104 and is shown received in the radialclearance described above. In one embodiment of the bearing 122, twoC-shaped bearing pieces 122-P are provided. The C-shaped pieces 122-Pare placed together to define a thick circle, or annular-shaped, ordonut-shaped, configuration. A fastener 124 such as a screw, extendsthrough each of two holes 126 adjacent to a bearing end 128 of the outerpipe 102. The screws 124 extend through the holes 126 and into therespective C-shaped piece 122-P to retain the respective one of theC-shaped pieces 122-P adjacent to such bearing end 128 and with theannular-shaped bearing 122 mounted over the inner pipe 104. The annular,or donut, -shaped configuration of the bearing 122 provides an accesshole 129 in which to receive the inner pipe 104. The outer diameter ofthe bearing 122 is configured to be about equal to, or somewhat lessthan, the outer diameter of the outer pipe 102, which as noted above isselected according to the diameter of the inner pipe 104 so as to allowa flow of the material from the bearing end 128, and into and throughthe radial clearance as described below.

Referring to FIGS. 1A–1C, with this configuration, and with the bearing122 fixed to the outer pipe 102, during relative movement between theinner pipe 104 and outer pipe 102 the bearing 122 may rub tightlyagainst the outside of the inner pipe 104. With the pipes 102 and 104operated at low pressure, the bearing 122 reduces the flow of thematerial into the material collection conduit from other than headers132 provided with header openings 140. Because the header openings 140are spaced across a width (not shown) of the basin 150 (FIG. 2A), thebearing 122 promotes sludge collection across the width of the basin150. While the bearing 122 rubs against the inner pipe 104 in thismanner, the bearing 122 also permits the relative movement between thepipes 102 and 104 in the telescopic relationship. In detail, the bearing122 allows the outer pipe 102 to be moved relative the inner pipe 104 ina movement (see arrow 112, FIG. 1A) referred to as traversing of theouter pipe 102, and allows the flow of the material from the bearing end128 into the material collection conduit 120 as described below.

The traversing of the outer pipe 102 facilitates similar traversing ofone or more of the headers 132 that are secured to the outer rigid pipe102. FIG. 1A shows three such headers 132, and shows an end 134 of theouter pipe 102 that is closed to facilitate operation of the headers132. However, more than one header 132 may be provided between one ofthe headers 132 that is near the left end 134 and another one of headers132 that is near the bearing end 128 of the outer pipe 102, so that thedesired flow rate of material and liquid (e.g., sludge) is achieved.Each header 132 is a hollow member such as a pipe or conduit. Anexemplary plurality of headers 132 is shown in FIG. 1A, as threeheaders, each being secured to the outer pipe, shown as one headersection on each of opposite sides of the outer pipe 102. Each of theheaders 132 may be configured according to U.S. Pat. No. 5,914,049. Suchconfiguration includes material and liquid inlet, or header, openings140 that facilitate collection of the material and liquid with thematerial. In terms of these openings 140, the bearing 122 shown in FIGS.1A and 1C need only be effective to limit the leakage of the sludge andliquid (the material) into the material collection conduit 120 throughthe bearing 122 (rather than having all the flow be through the openings140) to a flow about equal to the flow into one or two of these openings140. Based on this description of limiting the material going into thematerial collection conduit 120 through the bearing 122, it may beunderstood that the bearing 122 allows the flow of material through thebearing end 128 (FIG. 1B) of the outer pipe 102 into the radialclearance (i.e., allows a bearing flow) and the bearing flow is from thebearing end 128 into the material collection conduit 120. It may also beunderstood that such bearing flow into the radial clearance and into thematerial collection conduit 120 from the bearing end 128 is less thanthe flow through the headers 132 (i.e., header flow) because the headers132 are shown in FIG. 1A having more of the openings 140 than the one ortwo openings 140 described above with respect to the amount of thebearing flow allowed by the bearing 122.

Opposite outer ends of each header 132 are closed, and opposite innerends that are secured to the outer pipe 102 are open to permit thematerial and liquid to enter the outer pipe 102. The headers 132 arealso provided with rollers 142 which guide the headers 132 and the pipes102 and 104 as described below.

To provide adequate flow of the collected materials and liquid, theheaders 132 may be configured with various nominal (inside) diameters,which are selected according to the desired flow rate through thematerial collection conduit 120, and in particular through the part C2of the inner pipe 104. For example, the inner pipe 104 may have anominal diameter of about four inches and the outer pipe 102 a nominaldiameter of about six inches, for example, and two headers 132 may beprovided. Each header 132 may have a three inch nominal diameter. Withsuitably sized material and liquid collection openings 140 in the twoheaders 132, and with the bearing flow as allowed by the bearing 122 andas described above, this configuration will provide a flow rate of about250 gpm through the inner conduit 104. This example shows that theembodiments of the present invention may provide substantially more flowrate (i.e., 250 gpm) using the same nominal (four inch) diameter of theinner pipe 102 as the maximum diameter four inch nominal diameterflexible prior art hose that has the maximum 200 gpm flow rate and morehead loss.

FIG. 2A shows one of the systems 100 installed in a container, which istypically referred to as a basin 150. Details not essential to thesystem 100 are not shown, but it may be understood that the liquid andmaterials enter the basin 150, and depending on the type of basin 150,the materials in some manner make their way to a floor, or bottom 152 ofthe basin 150. For clarity of description, the materials and liquid arenot shown. When the materials accumulate on the bottom 152, the system100 serves to collect them and guide them from the basin 150. The basin150 is provided with opposite end walls 154. An end wall 154 on theexemplary right of the basin 150 is provided with an outlet hole 156that receives the inner pipe 104 of the system 100. The inner pipe 104is secured to the right wall 154, as by a coupler or fitting, such thatthe inner pipe 104 is fixed to the end wall 154. The hole 156 isadjacent to the bottom 152 so that the axial direction (arrow 112)extends close to, and parallel to, the bottom 152. The basin 150 isshown with a length L between the end walls 154. The length of the innerpipe 104 in the basin 150 has a value of about ½ L as shown in FIG. 2A.The system 100 is also shown with the outer pipe 102 in theabove-described telescopic relationship with the inner pipe 104. Thus,the outer pipe 102 extends over the inner pipe 104. The rollers 142shown in FIG. 1A engage the side walls (not shown) and bottom 152 of thebasin, roll through the sludge, and keep the bottom of the outer pipe102 an exemplary few inches above the bottom 152. The outer pipe 102 isshown with an exemplary two headers 132, and the headers 132collectively extend across a width (not shown) between the side walls ofthe basin 150.

In FIG. 2A the outer header 102 is shown in the collapsed position,fully on (or covering) the inner pipe 104, in contrast to the positionshown in FIG. 1A. In this collapsed position, the rightward header 132is adjacent to the right end wall 154 and the leftward header 132 is inthe middle of the basin (between the end walls 154). A cable drive 160is provided to move the outer pipe 102 in the above-described traversingmovement relative to the inner pipe 104. The cable drive 160 may includea first cable 162 connected to the right (outlet) end 128 of the outerpipe 102, and a second cable 164 connected to the left end 134 of theouter pipe 102. The cables 162 and 164 are alternately moved left andright by a shared-reel drive described in U.S. Pat. No. 5,655,727,issued on Aug. 12, 1997, and entitled “Sludge Collector Method and DriveWith Shared Reel For Taking Up and Paying Out Cables”, the disclosure ofwhich is incorporated by reference. The cable drive 160 moves the outerpipe 102 to the left from the collapsed position shown in FIG. 2A to theextended position shown in FIG. 2B. The rollers 142 again roll over thefloor 152 and against the side walls, and the headers 132 move throughand into the sludge that is on the floor 152.

Installation of the system 100 may be understood from FIG. 2A. With thelength of each separate one of the pipes 102 and 104 generally the same,and ranging from about 20 to about 100 feet, the length of each pipe 102and 104 depends on such factors as the length of the basin 150, whichmay range from about 40 to about 200 feet between the end walls 154. Toinstall the system 100 in an existing basin 150 in which the equipmenthas been previously installed, shorter length outer and inner pipes 102and 104, respectively, are used. Thus, for a 100 foot long basin 150 inthe configuration shown in FIG. 2A, the outer pipe 102 may be in 20 footlengths and the inner pipe 104 may be in 20 foot lengths. The headers132 will have been secured to the appropriate lengths of the outer pipe102, such as at a factory. The lengths of the outer pipe 102 are placedin the basin 150 under the equipment, or near the bottom 152, and theflanges 121 are secured together. The lengths of the inner pipe 104 areplaced in the basin 150 under the equipment, or near the bottom 152, andare secured together, as by welding or gluing described below. The outerpipe 102 and the inner pipe 104 may be oriented at a diagonal relativeto the end walls 154 of the basin 150 and the outlet end 128 of theouter pipe 102 is placed over an inlet end 166 of the inner pipe 104 toachieve the telescopic relationship. The two pipes 102 and 104 are thenmoved into position about centrally between the side walls (not shown)of the basin 150 and an outlet end 168 of the inner pipe 104 is insertedthrough the end wall 154 (e.g., the rightward end wall 154 in FIG. 2A).

FIG. 2B shows the outlet end 168 of the inner pipe 104 extending outsidethe basin 150. The outlet end 168 is connected to a valve and vacuumpump (not shown). The pump causes a low pressure to be applied to theoutlet end 168 of the inner pipe 104. That low pressure causes a lowpressure in the material collection conduit 120 defined by the pipes 102and 104, so that the sludge is caused to flow into the openings 140 inthe headers 132, and into the bearing end 128 of the outer pipe 102, asthe outer pipe 102 is traversed. According to the U.S. Pat. No.5,914,049 identified above, the sludge enters the headers 132 at atangent and assumes a helical flow path toward the outer pipe 102. Thesludge enters and flows through the outer pipe 102, and then enters andflows through the inner pipe 104 to the outlet end 168 of the inner pipe104. The sludge flows past the control valve (not shown) and to otherconduits outside the basin 150 for collection and draining of the liquidto form dry sludge. When the outer pipe 102 reaches the left end wall154 of the basin 150, the cable drive 160 reverses and the outer pipe102 is traversed to the right and to the fully collapsed position shownin FIG. 2A. The reversing and opposite traversal alternate through manycycles of collecting the material and the liquid.

FIG. 3A shows another embodiment of the system 100 in which one header132 is provided on the outer pipe 102. Also, an exemplary item ofequipment 170 is shown in a leftward section of the basin 150. Theequipment 170 is configured in the above-described position relative tothe bottom 152 of the basin 150 to provide a low-clearance height Hbetween the bottom 152 and a lower portion or bottom 172 of theequipment 170. For example, the low-clearance height H may be betweenthe floor 152 of the basin 150 and a bottom (not shown) of a stirringfacility of a flocculator, or between the floor 152 of the basin 150 andthe bottom of the plates of a plate settler. This clearance H may beabout two feet and is a source of the above-described problems with theprior flexible hoses, which problem is solved by the system 100. The lowprofile of the maximum vertical dimension DM of the system 100 easilyfits within the low-clearance height H, because the height of thelow-profile dimension DM designates the value less than thelow-clearance height H described above. In more detail, because the twopipes 102 and 104 are in the telescopic relationship, the two pipes 102and 104 and the cable drive 160 occupy less height than two separate(non-coaxial) pipes would occupy, and the telescopic pipes 102 and 104do not float above the bottom 152 of the basin 150. Moreover, thepositions of the cables 162 and 164 in FIGS. 2A, 2B, 3A and 3B areexemplary for clarity of illustration, whereas in practice the cable 162and 164 may actually run in the sludge at the bottom 152 of the basin150 (and thus take up less vertical dimension DM).

In FIG. 3A the outer pipe 102 is shown in the extended position,opposite to the collapsed position shown in FIG. 2A. The inner pipe 104is shown extending through and fixed to the right end wall 154 of thebasin 150. Thus, the outer pipe 102 is in the fully extended position toshow another configuration of the pipes 102 and 104 in the basin 150. Inthis extended position, the one exemplary header 132 is adjacent to theleft end wall 154 and the outer pipe 102 is under the bottom 172 of theequipment 170 within the space provided by the low-clearance height H.The cable drive 160 is shown with the first cable 162 connected to theright end of the outer pipe 102, and the second cable 164 connected tothe left end of the outer pipe 102. The cables 162 and 164 are operatedin the same manner as described above to traverse the outer pipe 102.

FIG. 3B shows that the cable drive 160 moves the outer pipe 102 to theright from the extended position shown in FIG. 3A to the collapsedposition shown in FIG. 3B. Again, the rollers 142 roll over the floor152 and side walls (not shown) and the header 132 moves through and intothe sludge that is on the floor 152. The header 132 and, as describedabove, the bearing end 128 of the outer pipe 102, collect the sludge.FIG. 3B shows the outlet end 168 of the inner pipe 104 extending outsideof the basin 150 (past the right end wall 154), and the connections tothe pump are the same as described above. As the header 132 movesthrough the sludge, the sludge and liquid enter and flow through theouter pipe 102, and enter the bearing end 128 of the outer pipe 102 andflow through the radial clearance between the outer pipe 102 and theinner pipe 104, and then enter and flow through the inner pipe 104 tothe outlet end 168 of the inner pipe 104. When the outer pipe 102reaches the right end 154 of the basin 150, the cable drive 160 reversesand the outer pipe 102 then traverses to the left and back to the fullyextended position shown in FIG. 3A. The reversing and opposite traversalalternate through many cycles of collecting the material. It may beappreciated that with only the one exemplary header 132 as shown inFIGS. 3A and 3B, the header 132 of the system 100 only collects (orremoves) the sludge from the portion of the basin 150 under theequipment 170. That header collection is, however, supplemented as thefirst pipe 102 is traversed relative to the second pipe 104. In detail,as described above, the bearing 122 at the bearing end 128 of the firstpipe 102 allows the bearing flow of the material through the bearing122. With a value of about equal to the flow into one or two of theopenings 140, the bearing flow collects the material that is adjacent tothe pipes 102 and 104.

FIG. 4 shows details of the fastener 124 that secures the annularbearing 122 to the outer pipe 102. Also shown is the inner pipe 104supported on the bearing 122, which in turn is supported and carried bythe outer pipe 102. It may be understood that with only one bearing 122provided between the two pipes 102 and 104, the outer pipe 102 is freeto move between the fully extended position and the collapsed position.Also, to provide the outer surface of the inner pipe 104 with a smoothconfiguration against which the bearing 122 rubs and slides, the innerpipe 104 may be provided and configured as an assembly of short pipesthat are connected by an inner sleeve 180, for example, show generallyin FIG. 4. For clarity of illustration, the inner sleeve 180 is shown asone circular line, whereas the inner sleeve 180 would be about 0.083inches in wall thickness. Also, the inner surface of the inner pipe 104may be slightly recessed to provide a thin slot in which the innersleeve 180 may be received. The inner sleeve 180 may be secured to theinner pipe 104 as by adhesive or welding, for example.

FIG. 5 shows another embodiment of the system 100 also configured to beused in the basin 150 having the spaced opposite end walls 154. Thewalls 154 may be referred to as first and second end walls 154. Thefirst end wall 154 is shown on the left of FIG. 5 and the second endwall 154 is shown on the right. The second rigid pipe 104 is configuredto extend from the first (left) end wall 154 to the second (right) endwall 154. The second pipe 104 is configured with opposite ends 189 thatare supported adjacent to each of the end walls 154, as by being securedto each wall 154, as shown in FIG. 5, or being supported by a mount (notshown) that is on the bottom 152 adjacent to each of the end walls 154.The first pipe 102 may be configured to extend in the telescopicrelationship with respect to the second pipe 102 along a distance 190that is greater than half of the length L of the basin 150 between theend walls 154. The second pipe 104 may also be configured with amaterial collection opening 192 located between the ends 189. Thematerial collection opening 192 is provided through which to receive thematerial from the first pipe 102 under the action of the low pressureapplied to the second pipe 104. The respective first and second pipes102 and 104 are configured so that in the telescopic relationship thefirst pipe 102 has the opposite ends 128 and 134. Also, the first pipe102 is always outside and coaxial with at least a portion of the secondpipe 104, wherein the portion is about equal to the distance 190. One ofthe bearings 122 is provided at each of the opposite ends 128 and 134 ofthe first pipe 102. The bearings 122 provide the above-describedfunctions, which include allowing the above-described bearing flow ofthe material into the bearing end 128 of the outer pipe 102, andcomparable bearing flow of the material into the other bearing end 134of the outer pipe 102, as the outer pipe 102 is traversed. The materialis received by the first pipe 102 from the headers 132 and from the ends128 and 134 through the respective bearings 122. The material then flowsthrough the second pipe 104 out of the basin 150 as described above.Thus, in this embodiment, the material collection conduit 120 alsoincludes the material collection opening 192 through which the materialis received from the first pipe 102. In this embodiment, the first pipe102 is configured with the length 190 that exceeds half of a length L ofthe basin 150 between the opposed end walls 154. This length 190 assuresthat the opening 190 in the second pipe 104 is always covered by thefirst pipe 102. Also, the header 132 located adjacent to the end 134 ofthe first pipe 102 need only traverse substantially less than the lengthL of the basin 150 because the second header 132 at the end 128 of thefirst pipe 102 will collect material from the bottom 152 as the otherheader 132 collects the material. As described above, it may beappreciated from FIG. 5 that the bearing 122 at each of the oppositeends 128 and 134 of the first pipe 102 allows the bearing flow of thematerial through each of the bearings 122 rather than having all theflow be through the openings 140, and this bearing flow allowed by eachbearing 122 is about equal to the flow into one or two of the openings140. As a result, the combined value of the bearing flows allowed by thetwo bearings 122 is about equal to a flow through four of the openings140 of the plurality of openings 140.

It may be understood that this embodiment of the system 100 isespecially suited to basins 150 having a very long length L, which maybe up to about 200 or more feet. With the opposite ends 189 of thesecond pipe 104 secured in a fixed manner adjacent to the end walls 154of the basin 150, and with closure of the end 189 that does not extendthrough the right end wall 154, the first pipe 102 in effect rides alongand is guided by the second pipe in the axial direction 112 (FIG. 1A)and throughout the distance of the traverse of the first pipe 102. Insuch traverse, at least one header 132 passes over each location of thebottom 152 of the basin 150 and collects the material with liquid asdescribed above. The material and liquid flow through the headers 132and into the material collection conduit 120. In detail, from theheaders 132 the material and liquid flow into the first pipe 102,through the material collection opening 192 and into the second pipe 104to be guided out of the basin 150. Similarly, as the first pipe 102 isguided by the second pipe 104, the bearing 122 at each of the oppositeends 128 and 134 of the first pipe 102 allows the bearing flow of thematerial through each of the bearings 122, and this bearing flow allowedby each bearing 122, which is about equal to the flow into one or two ofthe openings 140, collects the material that is adjacent to the pipes102 and 104.

It may be understood, then that the system 100 of the embodiments of theinvention meets all of the above-described needs by providing a way ofsignificantly increasing the flow rate through the headers 132 thatcollect the material and liquid without causing the above-describedproblems in priming the sludge collection system 100. This results fromthe telescopic pipes 102 and 104 staying in a line of the axialdirection 112 adjacent to the bottom 152, and thus not floating upwardlyinto or against the bottom 172 of the equipment 170 (FIG. 3A), forexample. The system 100 of the embodiments of the present invention alsoprovides the described way of achieving such sludge collection, whilehaving an easily primed collection system, and providing the entiresludge collecting system in the space of the low-clearance height Hunder the bottom 172 of the settler and flocculating equipment 170 thatextends downwardly near the bottom 152 of the basin 150. The way ofsignificantly increasing the flow rate through the header 132 thatcollects the material and the liquid from the bottom 152 is by using thetelescopic pipes 102 and 104, which define a larger-diameter pipeassembly connected to the headers 132 than the prior flexible hoses. Theway of avoiding the problems in priming the sludge collection system 100is by making this telescopic pipe system 100 (that forms thelarger-diameter pipe assembly) rigid so that it is not free to rise(float) above the level of the headers 132 or the outlet end 168 of theinner pipe 104 in the basin 150. The way of achieving such sludgecollection, while having the easily primed collection system, andproviding the entire sludge collecting system 100 in the space of thelow-clearance height H under the bottom 172 of the settler andflocculating equipment 170 that extends down near the bottom 152 of thebasin 150, is by mounting the telescopic pipes 102 and 104 (that definethe larger-diameter, rigid pipe assembly) directly adjacent to thebottom 152 of the basin 150, e.g., along the traverse path 130 taken bythe headers 132 as they traverse the bottom 152 of the basin 150. Theway of achieving these features, while still allowing the sludgecollecting system 100 to traverse the headers 132 from one end wall 154of the basin 150 to the opposite end wall 154 of the basin 150, is bymaking this larger-diameter rigid pipe assembly telescopic, that is, byproviding the telescopic relationship between the two pipes 102 and 104.In this manner, one telescoping pipe 104 is secured or fixed to thebasin 150, as by being held in place as it extends through the end wall154 of the basin 150 to the outside of the basin 150. Such fixed pipe104 is the inner, larger-diameter pipe (measured relative to the small,e.g., maximum of four inches of the prior flexible pipes describedabove. The other telescoping pipe is the outer pipe 102, somewhat largerthan the inner fixed pipe 104 so as to receive the inner pipe 104 andpermit the relative movement between the two telescoping pipes 102 and104. The outer, movable, telescopic pipe 102 carries the headers 132 andis moved by the low-profile cable drive 160 relative to the bottom 152of the basin 150 and between the end walls 154 of the basin 150 topresent the headers 132 to the sludge that accumulates on the bottom 152of the basin 150 awaiting collection. The way of achieving thesefeatures, while allowing the sludge collecting system to both traversethe header 132, or headers 132, from one end of a very long basin to theopposite end of the very long basin and to collect the material from thebasin at locations between opposite ends of the headers, is to configurethe bearing 122 between the telescopic pipes 102 and 104 so as to allowadditional flow of the material in the radial clearance that is betweenthe telescopic pipes 102 and 104 and in which the bearing 122 isreceived. In this manner, the open bearing end 128 of the movable,large-diameter, outer pipe 102 serves as an additional materialcollector positioned at a location that is between opposite ends of theheader pipe 132.

Although the foregoing has been described in some detail for purposes ofclarity or understanding, it will be appreciated that certain changesand modifications may be practiced within the scope of the appendedclaims. Accordingly, the present embodiments are to be considered asillustrative and not restrictive, and the embodiments of the inventionare not to be limited to the details given herein, but may be modifiedwithin the scope and equivalents of the appended claims.

1. A system for collecting material, comprising: a first rigid pipe, thefirst rigid pipe defining a first conduit, the first rigid pipe having afirst open end; a second rigid pipe, the second rigid pipe defining asecond conduit, the second rigid pipe having a second open end; thefirst and second pipes being in telescopic relationship with the firstrigid pipe and the second rigid pipe being in an overlappingrelationship between the respective first and second ends of theoverlapping pipes, the overlapping relationship defining a radialclearance between the first rigid pipe and the second rigid pipe; atleast one header pipe secured to one of the rigid pipes, the at leastone header pipe having a first plurality of openings through which tocollect the material, the at least one of the header pipes directing thematerial to the one of the rigid pipes, wherein the first plurality ofopenings is configured to provide a first flow of the material from theheader pipe into the one of the rigid pipes, and a bearing received inthe radial clearance between the first rigid pipe and the second rigidpipe, the bearing being configured to allow a second flow of thematerial through the respective first or second open end and into theone of the rigid pipes and into the radial clearance to collectmaterial, wherein a value of the second flow is less than a value of thefirst flow.
 2. A system for collecting material as recited in claim 1,wherein the value of the second flow is about equal to a flow throughone or two of the openings of the plurality of openings.
 3. A system forcollecting material as recited in claim 2, wherein a number of the firstplurality of openings is greater than the one or two of the openings ofthe plurality of openings that results in the second flow.
 4. A systemfor collecting material as recited in claim 1, wherein the one rigidpipe is the first rigid pipe, the system further comprising: a drive fortraversing the first rigid pipe relative to the second rigid pipe sothat the first open end of the first rigid pipe moves relative to thematerial, during the relative movement the first open end receiving thesecond flow of the material.
 5. A system as recited in claim 4, whereinthe bearing allows the second flow of the collected material to occurfrom the first open end through the radial clearance and into the secondrigid pipe.
 6. A system as recited in claim 1, wherein the radialclearance has a value of about one to two inches and the bearing allowsthe second flow of the collected material to occur from the first openend through the radial clearance to join the first flow from the headerconduit for combined flow into the second rigid pipe.
 7. A system forcollecting material, comprising: an outer rigid pipe having a first openend; an inner rigid pipe having a second open end; the outer and innerrigid pipes being in telescopic relationship with the inner pipereceived within the outer pipe, the outer rigid pipe and the inner rigidpipe being in an overlapping relationship to define a radial clearancebetween the outer rigid pipe and the inner rigid pipe; at least oneheader pipe secured to the outer rigid pipe, the at least one headerpipe having a first plurality of openings through which to collect thematerial, the at least one header pipe defining a header conduitextending from the first plurality of openings to the outer rigid pipeto allow a first flow of the materials into the outer rigid pipe; and abearing received in the radial clearance and configured to allow asecond flow of the materials into the first open end and through theradial clearance and into the inner rigid pipe.
 8. A system forcollecting material as recited in claim 7, wherein a value of the secondflow is about equal to a flow through one or two of the openings of thefirst plurality of openings so that the value of the second flow is lessthan a value of the first flow.
 9. A system for collecting material asrecited in claim 7, the system further comprising: a drive fortraversing the outer rigid pipe relative to the inner rigid pipe so thatthe first open end of the outer rigid pipe moves relative to thematerial, the first open end collecting the material during the relativemovement.
 10. A system as recited in claim 7, wherein the radialclearance has a value of about one to two inches and the bearing allowsthe second flow of the collected material to occur into from the firstopen end through the radial clearance and into the inner pipe to joinwith the first flow.
 11. A system for collecting material, comprising:an outer rigid pipe having a first open end and a second end; an innerrigid pipe having a material receiving opening, the inner rigid pipebeing received within and spaced from the outer pipe by a radialclearance to permit movement of the outer pipe relative to the innerpipe; a header pipe secured to the outer pipe adjacent to each of thefirst and second open ends, each of the header pipes having a pluralityof openings through which to collect the material, each of the headerpipes defining a header conduit extending from the plurality of openingsto the outer rigid pipe and being configured to collectively permit afirst flow of the material into the outer rigid pipe; and a bearingreceived in the radial clearance and configured to allow both themovement of the outer pipe relative to the inner pipe and a second flowof the material into the second end and through the radial clearance;wherein the bearing is configured to control a value of the second flowrelative to a value of the first flow so that the material is collectedthrough the first open end and through each of the openings.
 12. Asystem for collecting material as recited in claim 11, wherein the valueof the second flow is about equal to a flow through two of the openingsof the plurality of openings.
 13. A system for collecting material asrecited in claim 11, the system further comprising: a drive fortraversing the outer pipe relative to the inner pipe so that the firstopen end of the outer rigid pipe moves relative to the material, thefirst open end collecting the material during the relative movement. 14.A system for collecting material as recited in claim 11 wherein: theinner pipe is configured to carry an aggregate flow of from about 20 gpmto about 2000 gpm of the material collected through the first open endand collected through each of the openings into the inner pipe.
 15. Asystem for collecting material, comprising: a basin having a bottom forsupporting the material, the basin being configured with equipment thatprovides the material supported on the bottom, the equipment beingconfigured in a position relative to the bottom to a providelow-clearance height between the bottom and a lower portion of theequipment; and a low-profile apparatus for collecting the material fromthe bottom of the basin, the low-profile apparatus comprising: an outerrigid pipe having a first open end and a second open end; an inner rigidpipe having a material receiving opening, the inner rigid pipe beingreceived within and spaced from the outer pipe by a radial clearance topermit telescopic movement of the outer pipe relative to the inner pipe;a header pipe secured to the outer pipe adjacent to each of the firstand second ends, each of the header pipes having a plurality of openingsthrough which to collect the material, each of the header pipes defininga header conduit extending from the plurality of openings to thematerial collection conduit and being configured to permit a first flowof the material into the material collection conduit; and a bearingreceived in the radial clearance adjacent to each respective first andsecond open end to permit the movement of the outer pipe relative to theinner pipe while allowing a second flow of the material through each ofthe first and second open ends and into the radial clearance.
 16. Asystem as recited in claim 15, wherein the bearing is configured tocontrol a value of the second flows relative to a value of the firstflow, wherein the combined value of the second flows is about equal to aflow through four of the openings of the plurality of openings, so thatthe material is collected through each of the first open end and thesecond open end and through each of the openings.
 17. A system forcollecting material as recited in claim 16, wherein the system isconfigured to be used in a basin having spaced first and second endwalls, and wherein: the inner rigid pipe is configured to extend fromthe first end wall to the second end wall.
 18. A system for collectingmaterial as recited in claim 17, wherein: the outer pipe is configuredto extend around the outer pipe along a distance greater than half alength of the basin between the end walls; and the inner rigid pipe isconfigured with a material collection opening through which to receivethe second flow of material collected through the first open end and thesecond open end and flowing into the radial clearance, the materialcollection opening also receiving the first flow of material collectedthrough each of the openings in the header pipes.
 19. A system forcollecting material as recited in claim 18 wherein: the inner pipe isconfigured to carry a flow of from about 20 gpm to about 2000 gpm of thematerial collected through the first open end, the second open end andthrough the openings.
 20. A system as recited in claim 17, wherein: theinner and outer pipes are configured so that the outer pipe has thefirst and second ends at opposite ends of the outer pipe, and the outerpipe is always outside and coaxial with at least a portion of the innerpipe, and the bearing is provided at each of the first and secondopposite ends of the outer pipe; and the portion of the inner pipe isconfigured with a material collection opening through which to receivethe second flow of material collected through the first open end and thesecond open end and flowing into the radial clearance, the materialcollection opening also being through which to receive the first flow ofmaterial collected through each of the openings in the header pipes.